scholarly journals THE PERFORMANCE OF DAIRY CATTLE GRAZING TWO VARIETIES OF TALL FESCUE

Author(s):  
G.F. Wilson

Two varieties of tall fescue were compared with 'Grasslands Ariki' ryegrass as feeds for lactating, and growing catmtle. In three shortterm experimeats the dairy cows grazing the different types of pasture produced similar quantities of milk and in most cases the fat and protein contents did not differ significantly. On the other hand, the exclusion of clover from the grass swards led to a lower milk production. Liveweight gains were consistently higher for yearling cattle grazing Ariki ryegrass compared with the two fescue swards. The invitro digestibility of S170 was lower than the value for G4710 but because of the high clover content of the S170 pastures animal performance was similar.

1986 ◽  
Vol 26 (5) ◽  
pp. 523 ◽  
Author(s):  
WJ Fulkerson ◽  
RC Dobos ◽  
PJ Michell

Intakes of metabolisable energy (ME) in grazed herbage, silage, hay and grain were measured in dairy cows on 2 farmlets during 2 consecutive 12-month periods. Measured intakes were compared with predicted 'requirements' for ME, calculated by using values for liveweight and milk production measured during the 2 periods. These results validate the use of standard energy allowances to predict ME requirements of dairy cattle grazing in an environment similar to that described here. The measured (mean � s.d.) ME intake was 95 � 6.7% of predicted requirements using standard energy allowances.


2021 ◽  
Vol 11 (1) ◽  
pp. 110-114
Author(s):  
Astin Islam Andriani ◽  
Sri Pantja Madyawati ◽  
Emy Koestanti Sabdoningrum

One of the causes of low reproductive efficiency in dairy cattle is the presence of reproductive disorders caused by a non-specific bacterial infection. The aim of the present study was to isolate and identify the genus of non-specific bacteria in the reproductive tract of dairy cattle during artificial insemination. A total of 10 samples in the form of mucus attached to the plastic sheath used after artificial insemination in dairy cattle were collected in the study. The samples were subjected to bacterial isolation and identification. The obtained results of the study indicated that Staphylococcus was the dominant genus found (90%). On the other hand, other genera were Escherichia (60%) and Corynebacterium (20%).


Game Theory ◽  
2017 ◽  
pp. 106-119
Author(s):  
Khaled Suwais

Representing players' strategies in game theory has a direct impact on the players' performance. The state of art shows that automata are one of the primary techniques used for representing players' strategies and behaviors. In this paper, the author will identify different types of automata and assess their utilization in the field of game theory. Is has been found that finite automata, adaptive automata, and cellular automata are widely adopted in game theory. The utilization of finite automata is found to be limited to represent simpler players' behavior. On the other hand, adaptive automata and cellular automata are intensively applied in complex environments, where the number of interacted players is large and therefore, representing complex behaviors are needed.


2007 ◽  
Vol 2007 ◽  
pp. 148-148
Author(s):  
A. Heravi Moussavi ◽  
M. Danesh Mesgaran ◽  
T. Vafa

Reproduction and milk production are the principal factors that are influencing dairy farm profitability. The dairy industry in Iran has changed dramatically in the last decade. The shift toward more productive cows and larger herds in Iran is associated with a decrease reproductive efficiency (Heravi Moussavi et al., 2004). Increased knowledge about the principal causes of reduced fertility is essential. The root cause of the declining fertility is probably a combination of a variety of physiological and management factors that have an additive effect on reproductive efficiency. Dairy cattle are inseminated and pregnancy is established while dairy cows are lactating. Based on the analyses of large datasets, there is clearly an antagonistic relationship between milk production and reproduction in dairy cattle (Lucy, 2001). It was shown that the hazard ratio for cumulative first 60-day milk yield and conception in high producer cows was 8 percent less than the others and also high milk yield was a risk factor for several reproductive disorders (Grohn and Rajala-Schultz, 2000). The objective of this study was to evaluate the effect of first 60-day cumulative milk yield on days open in Iranian Holstein dairy cows.


Author(s):  
C.S. Mayne ◽  
S.C.P. Woodcock ◽  
A.J. Clements

Buffer-feeding of grazing dairy cows, by allowing cows access to forage for a few hours each day, has been widely advocated as a means of maintaining high animal performance whilst enabling efficient sward utilization. However, in practice, responses to buffer-feeding with January/February calving cows have been extremely variable. The objective of this study was to examine if part of the variability in response could be explained by differences in the level of nutrition during the winter feed period.


2002 ◽  
Vol 2002 ◽  
pp. 154-154
Author(s):  
Teimouri Yansari A. ◽  
R. Valizadeh ◽  
A. Nasserian

Nearly 2.4 million tons of rice is consumed by Iranian(37kg/person/year). Generally, in rice cocking process the grain is boiled and drained and a large volume of rice water is produced. Rice water is content of 5%DM, 0.43% CP, 3.75% NFE and almost 2 Mcal/KgDM gross energy. This liquid as a product of drained processing can be utilized in animal feeding (Valizadeh et al. 2000). Two studies carried out to evaluated the differences levels of rice water and its effects on milk production, rumen and blood metabolites of dairy cows.


2001 ◽  
Vol 26 (1) ◽  
pp. 223-236 ◽  
Author(s):  
M. C. Lucy ◽  
B. A. Crooker

AbstractSelection of dairy cattle for increased milk production has decreased some indices of reproductive efficiency. For example, days open are increased by one day for every 100 kg of increased milk yield per lactation. Some of the change in days open can be explained by delayed onset of oestrous cyclicity and lower conception rate to artificial insemination in cows with greater milk production. Despite these negative associations between milk production and reproduction, reproduction in herds of high producing dairy cattle is not necessarily compromised relative to reproduction in herds of low producing dairy cattle. This is because there is a large environmental effect on dairy reproduction. High producing herds generally have better management and better oestrous detection. Therefore, high producing dairy herds may partially overcome the antagonistic relationship between milk production and reproduction. Physiological mechanisms that lead to poorer reproduction in high producing cows are partially defined. Negative energy balance that occurs in high producing dairy cows can be associated with a delay in the initiation of ovarian cycles and the interval to first breeding. Many of the effects of negative energy balance on postpartum reproduction can be explained by decreased serum luteinizing hormone (LH) that is associated with negative energy balance. Serum LH increases as cows move toward positive energy balance and greater LH stimulates growth and ovulation of ovarian follicles. We have initiated studies to address physiological differences in high and low index dairy cows. The reproductive endocrinology of cows from a control line (5,900 kg milk/lactation) and a select line (10,900 kg milk/lactation) of dairy cows at the University of Minnesota was studied over a two-year period. Cows in Year 1 were similar for serum concentrations of LH, follicle stimulating hormone (FSH), and oestradiol (preovulatory period). In both years, serum concentrations of progesterone during luteal phases, however, were decreased in select cows. The Year 2 cows also had a delay in the return to oestrous cyclicity that was associated with reduced LH. The possibility that decreased progesterone causes infertility in dairy cows will require further study. Collectively, these data suggest that changes in blood progesterone concentrations may explain, partially, lower fertility in high index dairy cows.


Molecules ◽  
2019 ◽  
Vol 24 (16) ◽  
pp. 2933 ◽  
Author(s):  
Ranajit Saha ◽  
Gourhari Jana ◽  
Sudip Pan ◽  
Gabriel Merino ◽  
Pratim Kumar Chattaraj

Noble gases (Ngs) are the least reactive elements in the periodic table towards chemical bond formation when compared with other elements because of their completely filled valence electronic configuration. Very often, extreme conditions like low temperatures, high pressures and very reactive reagents are required for them to form meaningful chemical bonds with other elements. In this personal account, we summarize our works to date on Ng complexes where we attempted to theoretically predict viable Ng complexes having strong bonding to synthesize them under close to ambient conditions. Our works cover three different types of Ng complexes, viz., non-insertion of NgXY type, insertion of XNgY type and Ng encapsulated cage complexes where X and Y can represent any atom or group of atoms. While the first category of Ng complexes can be thermochemically stable at a certain temperature depending on the strength of the Ng-X bond, the latter two categories are kinetically stable, and therefore, their viability and the corresponding conditions depend on the size of the activation barrier associated with the release of Ng atom(s). Our major focus was devoted to understand the bonding situation in these complexes by employing the available state-of-the-art theoretic tools like natural bond orbital, electron density, and energy decomposition analyses in combination with the natural orbital for chemical valence theory. Intriguingly, these three types of complexes represent three different types of bonding scenarios. In NgXY, the strength of the donor-acceptor Ng→XY interaction depends on the polarizing power of binding the X center to draw the rather rigid electron density of Ng towards itself, and sometimes involvement of such orbitals becomes large enough, particularly for heavier Ng elements, to consider them as covalent bonds. On the other hand, in most of the XNgY cases, Ng forms an electron-shared covalent bond with X while interacting electrostatically with Y representing itself as [XNg]+Y−. Nevertheless, in some of the rare cases like NCNgNSi, both the C-Ng and Ng-N bonds can be represented as electron-shared covalent bonds. On the other hand, a cage host is an excellent moiety to examine the limits that can be pushed to attain bonding between two Ng atoms (even for He) at high pressure. The confinement effect by a small cage-like B12N12 can even induce some covalent interaction within two He atoms in the He2@B12N12 complex.


Land ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 71
Author(s):  
Amorn Pochanasomboon ◽  
Witsanu Attavanich ◽  
Akaranant Kidsom

This article evaluates the impacts of land ownership on the economic performance and viability of rice farming in Thailand, and explores whether they are heterogeneous across different types of farming while using the propensity score matching (PSM) technique. This study categorizes land ownership into two types: full land ownership and weak land ownership. We reveal that full land ownership enhances the rice yield of small and midsize farms, with values of 115.789–127.414 kg/hectare and 51.926–70.707 kg/hectare, respectively. On the other hand, weak land ownership only enhances the rice yield of small farms, with an increased yield of 65.590–72.574 kg/hectare. Full land ownership also helps to reduce the informal debt of small and midsize farms by $16.972–$24.877 per farm and $31.393–$37.819 per farm, respectively. On the other hand, weak land ownership helps to reduce the informal debt of midsize farms, ranging from $36.909 to $44.681 per farm. Therefore, policy makers should encourage small and midsize farm households to adopt full land ownership instead of weak land ownership, as this will provide the greatest benefits to farm households and efficient land use.


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